Influence of Inertia on Inverse Fluidization in a narrow rectangular channel: An Experimental Study

The presence of particles in a flow can change the flow behaviour in an unpredictable manner, that leads us to multiphase flow. Multiphase flows are present in nature and in everyday life around us. The most common example of a multiphase flow, that one can think of, is the treatment of drinking water using liquid-solid fluidization in softening...

A High-Efficiency 4-Phase Series-Parallel Resonant Switched-Capacitor 48-to-3 V DC-DC Converter

Resonant switch-capacitor (ReSC) is a type of hybrid switched-capacitor (HSC) which utilizes both inductor and capacitor, bearing the potential to overpower conventional switched-capacitor (SC) and magnetic-based converters. This work introduces a novel four-phase series-parallel resonant switch-capacitor (ReSC) DC-DC converter topology, which...

The Time-Line: A multi-phase project in Friedrichshain, Berlin that responds to urban changes

In Friedrichshain, Berlin, modest architecture with minimal interventions is utilized as a thoughtful response to the complex social and economic issues, including gentrification, that characterize the constantly evolving environment. This architectural approach seeks to tackle these challenges by embracing a restrained and humble style, while...

Preliminary design methods for the thermal management of fuel cell powered aeroengines

Hydrogen fuel cells are set to play an important role in decarbonizing the aviation sector. They operate at higher efficiencies than turbine engines, but their low operating temperature requires a dedicated thermal management system. The added drag, weight and parasitic power of such a system has a high impact on aircraft performance and its...

High efficiency, highly integrated DC-DC converter for 48V data centers with standard CMOS and GaN devices

This thesis presents a 48V-to-1V 10-level dual inductor hybrid converter (DIHC) containing 11 on-chip switches and an off-chip Gallium Nitride (GaN) switch. Thanks to the 10-level Dickson switched-capacitor (SC) circuit, most of the voltage stress will be taken over by off-chip capacitors, which reduces the voltage stress of each switch to 4.8 V...

Numerical Investigation of Spray Formation in Air-Blast Atomizers: Numerical study of air-blast atomization using a hybrid volume of fluid/discrete phase solver

The conducted study investigates the potential of a newly released multi-phase solver to simulate atomization in liquid rocket injectors. The "VOF-to-DPM" solver was used to simulate primary and secondary atomization in an air-blast atomizer with a coaxial injector-like geometry. The solver uses a hybrid Eulerian/Eulerian-Lagrangian formulation...

Modeling and simulating three phases of steel: Austenite, ferrite and cementite

In the work of Den Ouden the level-set method has been used to model the growth and dissolution in a steel alloy of the precipitate cementite and the diffusive phase austenite. The movement of the interface between the two phases is controlled by the diffusion of carbon and a reaction on the interface between the two phases. In this thesis...

Design optimization of splitter blades for rocket engine turbopump

Turbopumps are used in large-scale liquid rockets to inject the cryogenic propellants into the combustor. The turbopumps operate at high rotational speed, which in turn leads to cavitation at the inlet of the impeller. Cavitation can cause performance issues, instabilities and mechanical damage of the blades.<br/>This thesis presents and...